Device for setting type carrying means in a printing device having at least one printing position, especially for cash registers

ABSTRACT

A setting device for a printing device, there being provided for each character location an electromagnet which is arranged to change state when a calculating unit has received a number of pulses corresponding to the symbol to be set. Each electromagnet is cooperating with a driven setting unit which is in turn cooperating with a type carrying means. The setting units are arranged side by side on a common, driven axle and have essentially smaller extension in the axial direction of the axle than in the radial direction of the same. Each setting unit disengages a central means in the setting unit from the axle when the corresponding electromagnet changes state. The axle reverses its direction of rotation for setting and resetting.

United States Patent Lundstriim et al.

[ Dec, 30, 1975 DEVICE FOR SETTING TYPE CARRYING MEANS IN A PRINTINGDEVICE HAVING AT LEAST ONE PRINTING POSITION,

ESPECIALLY FOR CASH REGISTERS Inventors: G'o'ran Ingemar Lundstr'dm,

Johanneshov; Friedrich I-Iartmann, Saltsjobaden; Willem l-luijsers,Farsta, all of Sweden Hugin Kassaregister AB, Stockholm, Sweden Filed:Apr. 16, 1974 Appl. No.: 461,354

Assignee:

Foreign Application Priority Data Apr. 17, 1973 Sweden 7305458 U.S. Cl.235/61 PK; 235/60 P Int. Cl. G06C 29/00; G06C 11/04 Field of Search235/61 PK, 59 BF, 61 PJ,

References Cited UNlTED STATES PATENTS 6/1958 Ash et al 101/93252,896,845 7/1959 Hansen et al. 235/61 PK 3,022,939 2/1962 Flagge 235/61PK 3,097,789 7/1963 Kassel et al 235/61 PK 3,176,610 4/1965 Benson etal...... 101/9318 3,179,044 4/1965 Schierbeek.... 101/9328 3,691,3609/1972 Gross et al 235/61 PK Primary Examiner-Stephen J. TomskyAttorney, Agent, or Firm-Cushman, Darby & Cushman [57] ABSTRACT Asetting device for a printing device, there being provided for eachcharacter location an electromagnet which is arranged to change statewhen a calculating unit has received a number of pulses corresponding tothe symbol to be set. Each electromagnet is cooperating with a drivensetting unit which is in turn cooperating with a type carrying means.The setting units are arranged side by side on a common, driven axle andhave essentially smaller extension in the axial direction of the axlethan in the radial direction of the same. Each setting unit disengages acentral means in the setting unit from the axle when the correspondingelectromagnet changes state. The axle reverses its direction of rotationfor setting and resetting.

6 Claims, 4 Drawing Figures US. Patent Dec. 30, 1975 DEVICE FOR SETTINGTYPE CARRYING MEANS IN A PRINTING DEVICE HAVING AT LEAST ONE PRINTINGPOSITION, ESPECIALLY FOR CASH REGISTERS The present invention relates toa device for setting typecarrying means in a printing device having atleast one printing position, especially for use in cash regis ters, saiddevice comprising a pulse generating means which emits pulses to acalculating or counting unit and also comprising an electromagnet foreach of the character locations, said electromagnet being arranged tochange its magnetic state when the calculating unit has received apredetermined number of pulses from the pulse generating means, saidnumber of pulses corresponding to the symbol which is to be set and inwhich device a driven setting unit is provided for each electromagnet,said setting unit being arranged to cooperate with a type carrying meansof each respective character location.

Such devices for setting type are previously known in variousembodiments. That which the majority of these previously known deviceshave in common is that their construction is extremely complicated bymeans of a large number of axles upon which mutually cooperating unitsare arranged, said units requiring great space and, further, limitingthe number of character locations which are to be set. Due to thespace-demanding design, special transfer gears are required in order totransfer the setting movement to the type-carrying means. This furtherincreases the demands for space. Another disadvantage is that themoveable masses become rather large, causing problems during the highspeed of the setting process. The great number of parts furtherincreases the noise level when in operation and also impairs accuracy.This is a great disadvantage, for instance when the printed products areto be optically read.

The purpose of the present invention is to eliminate the above-mentionedproblems and disadvantages and instead obtain a setting device which issimple and takes up little space and also makes possible accuratesetting of a large number of character locations at several printingpositions in a printing device.

This is achieved according to the invention by means of the settingunits being arranged side by side on a common driven axle, said settingunits having essentially lesser extension in the axial direction of theaxle than in the radial direction of the same, and that one singlesetting unit is provided for each character location, said setting unitbeing arranged to, when its accompanying electromagnet changes state asa result of the calculating unit having received a predetermined numberof pulses, disengage a central means in the setting unit from the drivenaxle, said central means cooperating with the type-carrying means of theprinting location or locations. The driven axle is arranged to rotate inopposite directions during setting and resetting of said type-carryingmeans. By means of each setting unit only requiring a small space inaxial direction, a large number of setting units can be fitted on thesame driven axle and, thus, it is possible to use a large number ofcharacter locations without the dimensions of the device becoming toogreat.

According to an especially advantageous embodiment, the central means ofeach setting unit is in direct engagement with the type-carrying meansof its respective character location. Beyond a compact design anincreased setting accuracy is, in this manner, gained. However, spacereasons can make it necessary to use some form of transfer to one ormore printing positions which, unlike the others, cannot be placed nearthe driven axle.

A simple embodiment is obtained when the central means of each settingunit comprises a central wheel which rotates on the driven axle, saidcentral wheel being provided with teeth along at least a portion of itsperiphery, said central wheel supporting a retaining mechanism arrangedto cooperate with a driver which is permanently arranged on the drivenaxle and included in the setting unit. The retaining mechanismcooperates with the driver in order to lock and disengage the centralwheel in relation to the driven axle.

Further advantages and advantageous embodiments are revealed in theaccompanying description and claims.

A better understanding of the features and advantages of the inventionwill be had with the help of the following detailed description and theaccompanying detailed drawing, in which FIG. 1 shows a schematic sideview of a cash register equipped with a device according to theinvention, FIG. 2 shows a setting device according to the invention inthe initial position, FIG. 3 shows the setting device according to FIG.2 in a set position, and FIG. 4 shows a sectional view of the devicealong the line IV-IV in FIG. 2.

A cash register 1, in which only those details essential for theinvention are schematically shown, is according to FIG. 1 equipped witha printing device 2 having three different printing locations 3, 4 and 5which print receipts, audit strips and bills, respectively. A keyboard 6is connected to an electronic counting unit 7 for processing ofinformation which is introduced into the cash register via saidkeyboard. The counting unit 7 is in turn connected to a setting device 8whose function is to set the type-bearing means in the printing deviceso that printing can take place when the desired setting is accomplishedfor different character locations in the printing device.

Included in the setting device 8 is a driven axle 9 which, via a drivinggear (not shown here), is driven by a driving motor (not shown here)which also drives the printing device and other parts in the cashregister. A perforated pulse wheel 10, synchronized with the axle 9,together with a device 11 connected to the counting unit and comprisingfor example a light source and a photo cell, forms a pulse generatingunit. On the driven axle 9 there are arranged side by side a number ofsetting units 12 of which only one is visible, said number correspondingto the number of character locations in the printing device. For eachsetting device there is an electromagnet 13 connected to the countingunit 7. The setting units 12 have, as is clear from FIG. 4, only a smalldimension in the longitudinal direction of the axle 9. The result isthat all of the electromagnets, because they have a larger extension inthe longitudinal direction of axle 9 than each of the setting units,cannot be situated in the same row. In the embodiment shown here theelectromagnets in the upper row 14 cooperate with setting units 12having even position numbers while the electromagnets in the lower row15 cooperate with setting units having odd position numbers.

The design of one of the mutually identical setting units 12 is shownmore closely in FIG. 2. A central means 16 in the form of a centralwheel which is rotatable about the driven axle 9 and which is, at leastin part, provided with cogs 17 on its periphery, is in direct engagementwith symbol-carrying means in the form of type wheels 18, 19 and 20 foreach of the respective printing positions 3, 4 and 5. A driver 21 isaffixed to the axle 9 and is prevented from rotating by means of a pinor other means. Said driver cooperates with a retaining mechanism 22mounted on the central wheel 16 for locking and disengaging the centralwheel 16 and the driven axle 9. The retaining mechanism 22 includes aretaining ring 23 concentric with and attached to the central wheelwhich is limited in rotation by means of pins 24 attached to the centralwheel and engaging slots 25 in the retaining ring 23. The lockingmechanism further comprises two pivotally mounted, conjointly operatingpawls, an outer pawl 26 and an inner pawl 27 and a pivotable, journalledmagnet ratchet 28 which is actuated by and belongs to an electromagnet.The retaining ring 23 is internally fitted with a lock boss 29 whichcooperates with the outer pawl 26.

The inner pawl 27 is fitted with a dog 30 for engagement with a notch 31in the driver 21. On the central wheel there is a resetting dog 32 whichis designed to engage a resetting arm 33 on the driver. The resettingdog provides, in addition, support for one end of a curved spring 34which is supported at its other end in a notch 35 in the retaining ring23 and which strives to rotate the retaining ring and the central wheelto a position where the inner pawl 27, when the driver 21 is in acertain position, is forced to engage the notch 31.

The device operates in the following way.

At the beginning of the setting motion, the parts assume the resetposition shown in FIG. 2 when the drive axle begins to rotate clockwisein the direction of arrow 36. The inner pawl 27 is held in engagementwith the driver 21 via the lock boss 29 of the retaining ring 23 and theouter pawl 26, thereby causing the central means 16 to rotate and thusturn the type wheels 18, 19 and 20. Meanwhile, the counting unit 7receives pulses from the pulse generating unit. When the number ofreceived pulses corresponds to the number of pulses representing thesymbol to be set at the character location in question, the countingunit 7 actuates the electromagnet 13 altering its state and therebycausing the magnet ratchet 28 to turn. Depending on the design of themagnet ratchet 28, this can be achieved by energizing'the electromagnetwhich was previously not energized, or by deenergizing the electromagnetwhich was previously energized. The magnet ratchet 28 is thereby engagedwith the desired cog 37 on the retaining ring and checks furtherrotation of the retaining ring as per FIG. 3. The central wheelcontinues its rotation to an extent which corresponds to the length ofslot 25. The inner pawl 27 whose dog 30 is operated by the driver 21can, since the outer pawl 26 is no longer obstructed by the lock boss29, rotate outwards and disengage the central wheel 16 from driver 21when the parts assume the position shown in FIG. 3. Since the pawls 26and 27 are pressed outward toward the retaining ring, a gradual brakingof the central wheel is accomplished, thus avoiding a recoil which is togreat advantage at high speed.

Meanwhile, the driven axle and the driver continue to rotate though atmost one revolution from the start position, allowing the setting to becompleted for those setting units which have not yet assumed the desiredposition. When all setting units have completed their setting movement,an aligning device 38 is engaged with the central wheels, thus causingthe central wheels and thereby the type wheels to be carefully alignedand kept in position, allowing printing with high precision. Driven axle9 is now stationary. When resetting, the driven axle 9 is caused torotate counter-clockwise in the direction of arrow 39, and the aligningdevice 38 is disengaged. After a while, the resetting arm 33 of thedriver engages the resetting dog 32 of the central wheel and turns thecentral wheel so that the retaining mechanism 22 can reassume theposition shown in FIG. 2 whereby the central wheel reengages the driveaxle and continues back to the start position where a retaining boss 40on the retaining ring comes to bear on a stop 41. The magnet ratchet 28can be disengaged by means 7 of the retaining ring when the retainingring begins its return movement, or it can be disengaged by other meansobvious to one skilled in the art. After this, the setting unit is readyto commence a new setting movement.

Each retaining ring requires only as many cogs 37 as would correspond tothe number of symbols which will be set, but for practical reasons itmay be desirable to make all retaining rings identical. It should beobserved at this point that already in the start position the number Oor another symbol can be set. Because there is room for a large numberof setting units on the driven axle, the number of electromagnets can belarge and thus, it is desirable that the consumption of power by theelectromagnets be reduced. This can be accomplished by energizing theelectromagnets for as short a time as possible. Further, depending onthe placement and frequency of application of commonly used symbols, onecould choose to energize only certain electromagnets at the beginning ofthe setting movement, the remaining being dead and thus, only theelectromagnets for which setting will take place need to be suppliedwith current.

The design described herein can, of course, be modified in severalaspects. By way of example, the outer and inner pawls 26 and 27 can bereplaced by a single pawl which operates on driver and retaining ringsurfaces of a design other than that shown here. The number of printingpositions can be greater or fewer than shown here.

What we claim is:

1. A device for setting type-carrying means in a printing device havinga printing position, especially for cash registers, said devicecomprising a pulse generating means which emits pulses to an electroniccounting unit and also comprising an electromagnet for each of thecharacter locations, said electromagnet being arranged to change itsmagnetic state when the counting unit has received a predeterminednumber of pulses from the pulse generating means, said number of pulsescorresponding to the symbol which is to be set, and in which device adriven setting unit is provided for each electromagnet, said settingunit being arranged to cooperate with a type-carrying means of eachrespective character location, the setting units being arranged side byside on a common driven axle and have lesser dimension in the axialdirection of the axle than in the radial direction of the same, therebeing provided one single setting unit for each character location, saidone setting unit being arranged to, when its accompanying electromagnetchanges state as a result of the counting unit having received apredetermined number of pulses, disengage a central means in the settingunit from the driven axle, said central means cooperating with thetype-carrying means of the printing location, the central means at eachsetting unit comprising a central wheel which is rotatable on the drivenaxle and which is provided with teeth along its periphery, said :entralWheel supporting a retaining mechanism which 18 arranged for locking anddisengaging the central wheel in relation to the drive axle, saidretaining mechanism cooperating with a driver which is mounted on thedrive axle, said retaining mechanism including a retaining ring which ismounted on one side of the central means, said retaining ring beingrotatable to a limited extent in relation to the central wheel and alsobeing concentric to said central means, said retaining ring on its outerperiphery being provided with a number of engagement means forcooperation with the electromagnet, the inner periphery of saidretaining ring being provided with a locking boss for cooperation withan outer pawl which is pivotable on the central wheel, an inner pawlbeing arranged to be in or out of engagement with the driver dependingon the position of the outer pawl in relation to the locking boss of theretaining ring, the inner pawl and the outer pawl each being comprisedof an arm which is journalled at one end, said arms being arranged to beturned outwards away from the driven axle and disengage the central 6means as the rotation of the retaining ring is stopped by means of theelectromagnet, the retaining ring being thereby turned to adisengagement position in relation to the central means.

2. A device according to claim 1 wherein the central means and theretaining ring are actuated by a spring which attempts to turn theretaining ring to a locking position in which the retaining mechanism isengaged with the driver, said spring being located radially inwards ofthe inner periphery of the retaining ring.

3. A device according to claim 1 wherein the central means is providedwith a resetting dog which is arranged to be brought into engagementwith a resetting arm on the driver during resetting.

4. A device according to claim 1 wherein the central means are arrangedto be aligned by means of an alignment means after setting.

5. A device according to claim 1 the driven axle is arranged to rotatein the opposite directions during setting and resetting, respectively,of said type-carrying means.

6. A device according to claim 1, the central means of each setting unitis in direct engagement with the type-carrying means of its respectivecharacter location.

1. A device for setting type-carrying means in a printing device havinga printing position, especially for cash registers, said devicecomprising a pulse generating means which emits pulses to an electroniccounting unit and also comprising an electromagnet for each of thecharacter locations, said electromagnet being arranged to change itsmagnetic state when the counting unit has received a predeterminednumber of pulses from the pulse generating means, said number of pulsescorresponding to the symbol which is to be set, and in which device adriven setting unit is provided for each electromagnet, said settingunit being arranged to cooperate with a type-carrying means of eachrespective character location, the setting units being arranged side byside on a common driven axle and have lesser dimension in the axialdirection of the axle than in the radial direction of the same, therebeing provided one single setting unit for each character location, saidone setting unit being arranged to, when its accompanying electromagnetchanges state as a result of the counting unit having received apredetermined number of pulses, disengage a central means in the settingunit from the driven axle, said central means cooperating with thetype-carrying means of the printing location, the central means at eachsetting unit comprising a central wheel which is rotatable on the drivenaxle and which is provided with teeth along its periphery, said centralwheel supporting a retaining mechanism which is arranged for locking anddisengaging the central wheel in relation to the drive axle, saidretaining mechanism cooperating with a driveR which is mounted on thedrive axle, said retaining mechanism including a retaining ring which ismounted on one side of the central means, said retaining ring beingrotatable to a limited extent in relation to the central wheel and alsobeing concentric to said central means, said retaining ring on its outerperiphery being provided with a number of engagement means forcooperation with the electromagnet, the inner periphery of saidretaining ring being provided with a locking boss for cooperation withan outer pawl which is pivotable on the central wheel, an inner pawlbeing arranged to be in or out of engagement with the driver dependingon the position of the outer pawl in relation to the locking boss of theretaining ring, the inner pawl and the outer pawl each being comprisedof an arm which is journalled at one end, said arms being arranged to beturned outwards away from the driven axle and disengage the centralmeans as the rotation of the retaining ring is stopped by means of theelectromagnet, the retaining ring being thereby turned to adisengagement position in relation to the central means.
 2. A deviceaccording to claim 1 wherein the central means and the retaining ringare actuated by a spring which attempts to turn the retaining ring to alocking position in which the retaining mechanism is engaged with thedriver, said spring being located radially inwards of the innerperiphery of the retaining ring.
 3. A device according to claim 1wherein the central means is provided with a resetting dog which isarranged to be brought into engagement with a resetting arm on thedriver during resetting.
 4. A device according to claim 1 wherein thecentral means are arranged to be aligned by means of an alignment meansafter setting.
 5. A device according to claim 1 the driven axle isarranged to rotate in the opposite directions during setting andresetting, respectively, of said type-carrying means.
 6. A deviceaccording to claim 1, the central means of each setting unit is indirect engagement with the type-carrying means of its respectivecharacter location.